Accumulated Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ 646,458	$ 625,406	$ 643,867	$ 605,224
Reclassification from other comprehensive (income) loss			726
Other comprehensive income (loss)	(8)	39	(2)	(200)
Ending Balance	663,672	640,366	663,672	640,366
Unrealized Net Gains and (Losses) on Securities Available-for-Sale
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance			(726)	(612)
Other comprehensive income (loss), before reclassifications				(192)
Reclassification from other comprehensive (income) loss			726	178
Other comprehensive income (loss)			726	(14)
Ending Balance	0	(626)	0	(626)
Other comprehensive income (loss), before reclassifications, tax				77
Reclassification from AOCI, tax			(254)	(61)
Foreign Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance			(5)	12
Other comprehensive income (loss), before reclassifications			(2)	(8)
Reclassification from other comprehensive (income) loss			0	0
Other comprehensive income (loss)			(2)	(8)
Ending Balance	$ (7)	$ 4	(7)	4
Other comprehensive income (loss), before reclassifications, tax			$ 1	$ 2

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) before reclassification adjustment from accumulated other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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